Dasyleptus

Dasyleptus is an extinct genus of wingless insects in the order Archaeognatha, and the only member of the family Dasyleptidae. They resembled juveniles of their modern relatives and had a single lengthy filament projecting from the end of the abdomen. They also had a pair of leg-like cerci and some non-ambulatory abdominal appendages. The largest specimens reached 30 millimetres (1.2 in) or more, not counting the length of the filament. Dasyleptus species are mostly known only from the Late Carboniferous and Permian, but one species recorded from the Middle Triassic indicates that they survived the Permian–Triassic extinction event. Dasyleptus was formerly placed in its own extinct order, Monura, but is this is now treated as a suborder of Archaeognatha.